Railing for a dog treadmill



FIG. 1 is a perspective view of a railing for a dog treadmill showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a side elevational view thereof; and

FIG. 4 is a rear elevational view thereof.

The broken line representation of a dog treadmill in FIGS. 1 through 4 is for purposes of illustration only. 

The ornamental design for a railing for a dog treadmill, as shown and described. 